Vancouver Coastal Health is examining ways to better alert people about False Creek's water quality after boaters complained they were not made aware of health warnings.
The health authority for Metro Vancouver has issued two warnings since early July, saying the water at the east end of the creek is contaminated with coliform bacteria caused by sewage spills.
False Creek is not generally used for swimming, but is popular with kayakers and dragon boaters.
Many boaters didn't know about the health warnings and continued to use the water, said Andrea Dillon, a coach for the False Creek women's dragon boat team.
"When we had that spill in July, we didn't hear about it for two days," she told CBC News in a telephone interview on Tuesday.
"A lot of people can and do have immune-compromised systems like our organ transplant team [of boaters]," she said.
Signs were posted close to where the water was deemed contaminated, but Dillon said many people didn't see them.
Vancouver Coastal Health is trying to improve the way it alerts people about False Creek's water quality, said Domenic Losito, the authority's regional director of health protection.
"We are looking at compiling a list of boat launches and rental places, clubs and societies that use the water to get a rapid alert out to them.
He said the timing of the last spill, just before the long weekend, prevented health officials from alerting more people.
The health warning still in effect should be lifted for the eastern part of False Creek by the end of this week, Losito said.